Add __module__ and __qualname__ to methods, fix __name__

changelog.d/309.change.rst

@@ -0,0 +1 @@
+All generated methods now have correct ``__module__``, ``__name__``, and (on Python 3) ``__qualname__`` attributes.

src/attr/_make.py

@@ -491,43 +491,75 @@ def slots_setstate(self, state):
         return cls
 
     def add_repr(self, ns):
-        self._cls_dict["__repr__"] = _make_repr(self._attrs, ns=ns)
+        self._cls_dict["__repr__"] = self._add_method_dunders(
+            _make_repr(self._attrs, ns=ns)
+        )
         return self
 
     def add_str(self):
-        repr_ = self._cls_dict.get("__repr__")
-        if repr_ is None:
+        repr = self._cls_dict.get("__repr__")
+        if repr is None:
             raise ValueError(
                 "__str__ can only be generated if a __repr__ exists."
             )
 
-        self._cls_dict["__str__"] = repr_
+        def __str__(self):
+            return self.__repr__()
+
+        self._cls_dict["__str__"] = self._add_method_dunders(__str__)
         return self
 
     def make_unhashable(self):
         self._cls_dict["__hash__"] = None
         return self
 
     def add_hash(self):
-        self._cls_dict["__hash__"] = _make_hash(self._attrs)
+        self._cls_dict["__hash__"] = self._add_method_dunders(
+            _make_hash(self._attrs)
+        )
+
         return self
 
     def add_init(self):
-        self._cls_dict["__init__"] = _make_init(
-            self._attrs,
-            self._has_post_init,
-            self._frozen,
+        self._cls_dict["__init__"] = self._add_method_dunders(
+            _make_init(
+                self._attrs,
+                self._has_post_init,
+                self._frozen,
+            )
         )
+
         return self
 
     def add_cmp(self):
         cd = self._cls_dict
 
         cd["__eq__"], cd["__ne__"], cd["__lt__"], cd["__le__"], cd["__gt__"], \
-            cd["__ge__"] = _make_cmp(self._attrs)
+            cd["__ge__"] = (
+                self._add_method_dunders(meth)
+                for meth in _make_cmp(self._attrs)
+            )
 
         return self
 
+    def _add_method_dunders(self, method):
+        """
+        Add __module__ and __qualname__ to a *method* if possible.
+        """
+        try:
+            method.__module__ = self._cls.__module__
+        except AttributeError:
+            pass
+
+        try:
+            method.__qualname__ = ".".join(
+                (self._cls.__qualname__, method.__name__,)
+            )
+        except AttributeError:
+            pass
+
+        return method
+
 
 def attrs(maybe_cls=None, these=None, repr_ns=None,
           repr=True, cmp=True, hash=None, init=True,
@@ -753,7 +785,7 @@ def _add_hash(cls, attrs):
     return cls
 
 
-def _ne(self, other):
+def __ne__(self, other):
     """
     Check equality and either forward a NotImplemented or return the result
     negated.
@@ -807,15 +839,15 @@ def _make_cmp(attrs):
         unique_filename,
     )
     eq = locs["__eq__"]
-    ne = _ne
+    ne = __ne__
 
     def attrs_to_tuple(obj):
         """
         Save us some typing.
         """
         return _attrs_to_tuple(obj, attrs)
 
-    def lt(self, other):
+    def __lt__(self, other):
         """
         Automatically created by attrs.
         """
@@ -824,7 +856,7 @@ def lt(self, other):
         else:
             return NotImplemented
 
-    def le(self, other):
+    def __le__(self, other):
         """
         Automatically created by attrs.
         """
@@ -833,7 +865,7 @@ def le(self, other):
         else:
             return NotImplemented
 
-    def gt(self, other):
+    def __gt__(self, other):
         """
         Automatically created by attrs.
         """
@@ -842,7 +874,7 @@ def gt(self, other):
         else:
             return NotImplemented
 
-    def ge(self, other):
+    def __ge__(self, other):
         """
         Automatically created by attrs.
         """
@@ -851,7 +883,7 @@ def ge(self, other):
         else:
             return NotImplemented
 
-    return eq, ne, lt, le, gt, ge
+    return eq, ne, __lt__, __le__, __gt__, __ge__
 
 
 def _add_cmp(cls, attrs=None):
@@ -877,7 +909,7 @@ def _make_repr(attrs, ns):
         if a.repr
     )
 
-    def repr_(self):
+    def __repr__(self):
         """
         Automatically created by attrs.
         """
@@ -898,7 +930,7 @@ def repr_(self):
                 for name in attr_names
             )
         )
-    return repr_
+    return __repr__
 
 
 def _add_repr(cls, ns=None, attrs=None):
@@ -908,8 +940,7 @@ def _add_repr(cls, ns=None, attrs=None):
     if attrs is None:
         attrs = cls.__attrs_attrs__
 
-    repr_ = _make_repr(attrs, ns)
-    cls.__repr__ = repr_
+    cls.__repr__ = _make_repr(attrs, ns)
     return cls
 
 

tests/test_make.py

@@ -997,3 +997,49 @@ class C(object):
             .build_class()
 
         assert "ns.C(x=1)" == repr(cls(1))
+
+    @pytest.mark.parametrize("meth_name", [
+        "__init__", "__hash__", "__repr__", "__str__",
+        "__eq__", "__ne__", "__lt__", "__le__", "__gt__", "__ge__",
+    ])
+    def test_attaches_meta_dunders(self, meth_name):
+        """
+        Generated methods have correct __module__, __name__, and __qualname__
+        attributes.
+        """
+        @attr.s(hash=True, str=True)
+        class C(object):
+            def organic(self):
+                pass
+
+        meth = getattr(C, meth_name)
+
+        assert meth_name == meth.__name__
+        assert C.organic.__module__ == meth.__module__
+        if not PY2:
+            organic_prefix = C.organic.__qualname__.rsplit(".", 1)[0]
+            assert organic_prefix + "." + meth_name == meth.__qualname__
+
+    def test_handles_missing_meta_on_class(self):
+        """
+        If the class hasn't a __module__ or __qualname__, the method hasn't
+        either.
+        """
+        class C(object):
+            pass
+
+        b = _ClassBuilder(
+            C, these=None, slots=False, frozen=False, auto_attribs=False,
+        )
+        b._cls = {}  # no __module__; no __qualname__
+
+        def fake_meth(self):
+            pass
+
+        fake_meth.__module__ = "42"
+        fake_meth.__qualname__ = "23"
+
+        rv = b._add_method_dunders(fake_meth)
+
+        assert "42" == rv.__module__ == fake_meth.__module__
+        assert "23" == rv.__qualname__ == fake_meth.__qualname__